A 40-year-old patient from Bihar presents with painless progressive destruction of the nasal septum and palate, and stain of tissue biopsy shows intracellular organisms within macrophages on Giemsa stain (Leishman-Donovan bodies). The drug of choice and its primary mechanism is:
- A Sodium stibogluconate; impairs ATP and GTP synthesis in Leishmania amastigotes ✓
- B Suramin; inhibition of trypanosoma dihydrofolate reductase
- C Melarsoprol; reacts with trypanothione disrupting redox balance
- D Ivermectin; opens glutamate-gated chloride channels in protozoa
Correct answer: A. Sodium stibogluconate; impairs ATP and GTP synthesis in Leishmania amastigotes
Explanation
Sodium stibogluconate (pentavalent antimony) is the traditional drug of choice for visceral leishmaniasis; it impairs parasite energy metabolism by inhibiting enzymes involved in ATP and GTP biosynthesis in amastigotes. Suramin is used for African trypanosomiasis. Melarsoprol is used for late-stage sleeping sickness. Ivermectin targets helminth glutamate-gated chloride channels and has no activity against protozoa.
Reference: Ananthanarayan & Paniker's Textbook of Microbiology, 11th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.